Definition of "undulate" []

• To cause to move in a smooth wavelike motion. (verb-transitive)
• To give a wavelike appearance or form to. (verb-transitive)
• To move in waves or with a smooth, wavelike motion. See Synonyms at swing. (verb-intransitive)
• To have a wavelike appearance or form. (verb-intransitive)
• To increase and decrease in volume or pitch as if in waves. (verb-intransitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "These flat, white, square pieces of audio equipment--"They almost remind you of an empty white canvas," says Rudolf Frieling, SFMOMA's curator of media arts, who curated this piece -- rotate and undulate gracefully on pivot points, randomly directing laser-like beams of sound from the fifth-floor pedestrian bridge, which sits just under the museum's iconic circular skylight."
• "With the precision placement of bricks made possible by a robot, it ought to be possible to build a flat wall that would undulate in 3D when viewed as a stereogram."
• "The only part that required much thought was generating the floor polygons, which undulate back and forth between two shapes."